SOLVED: Adding error messages to an array in bash procedure - linux

Question

Here I placed working example, solved thanks to all you and completed with comments:
#!/bin/bash
errors=() #array to store all errors
to="" #a variable
DEST="" #another variable
from="" #and so on
e=$(mv "$from" "$to" 2>&1) #this command makes first error
if [ -n "$e" ] ;then errors+=("$e"); fi #and this save it to array
e=$(mv "$DEST" "$to" 2>&1) #so this makes second error
if [ -n "$e" ] ; then errors+=("$e"); fi #and this saves it to array
if [ ${#errors[#]} -eq 0 ]; then #if no errors
echo OK
else #if there are error (YES)
echo "ATTENZIONE: SI SONO VERIFICATI DEGLI ERRORI DURANTE L'OPERAZIONE DI RESTORE:"
for t in "${errors[#]}"; do #display all errors
echo "$t"
done
fi
Thank you very mutch.
This is the first answare before the solution:
I need to add to an array all error messages in my bash file.
Thanks to shellcheck.net and Cyrus and Freddy I adjusted code:
I did it:
#!/bin/bash
#set -x #DEBUG
errors=()
to=""
DEST=""
if ! mv "$from" "$to" ; then errors+=("$?"); fi
if ! mvv "$DEST" "$to" ; then errors+=("$?"); fi
if [ ${#errors[#]} -eq 0 ]; then
echo OK
else
echo "ATTENZIONE: SI SONO VERIFICATI DEGLI ERRORI DURANTE L'OPERAZIONE DI RESTORE:"
for t in "${errors[#]}"; do
echo "$t"
done
fi
the output that I obtain is :
ATTENZIONE: SI SONO VERIFICATI DEGLI ERRORI DURANTE L'OPERAZIONE DI RESTORE:
0
0
How can I do to obtain the right error messages in my array "$errors" ?
Thanks

Answer 1

The problem is that you aren't getting the exit status of the command (e.g. mv "$from" "$to"), but of the negated command (e.g. ! mv "$from" "$to") -- since the command failed (nonzero exit status), the negated status is success (zero). In order to do this, you need to avoid negating the status between the command and when you record the status. The easiest way I know of to do this is to use || instead of if, like this:
mv "$from" "$to" || errors+=("$?")